Instruction Manual

Instruction Manual
D100390X012
ED Valve
October 2014
15
5. Using an appropriate tool such as a center punch, stake the threads on top of the plug in one place (figure 9) to
secure the C-seal retainer.
6. Install the new plug/retainer assembly with C-seal plug seal on the new stem following the appropriate instructions
in the Trim Replacement section of this manual.
7. Install piston rings by following instructions in the Trim Replacement section of this manual.
8. Remove the existing valve actuator and bonnet following the appropriate instructions in the Replacing Packing
section of this m anual.
CAUTION
Do not remove the existing valve stem from the valve plug unless you are planning to replace the valve stem.
Never reuse an old valve stem with a new plug or reinstall a valve stem after it has been removed. Replacing a valve stem
requires drilling a new pin hole in the stem. This drilling weakens the stem and may cause failure in service. However, a
used valve plug may be reused with a new valve stem.
9. Remove the existing valve stem and plug, cage, and seat ring from the valve body following the appropriate
instructions in the Trim Removal section of this manual.
10. Replace all gaskets according to appropriate instructions in the Trim Replacement section of this manual.
11. Install the new seat ring, cage, valve plug/retainer assembly, and stem into the valve body and completely
reassemble the valve package following the appropriate instructions in the Trim Replacement section of this
manual.
CAUTION
To avoid excessive leakage and seat erosion, the valve plug must be initially seated with sufficient force to overcome the
resistance of the C-seal plug seal and contact the seat ring. You can correctly seat the valve plug by applying the full
actuator load. This force will adequately drive the valve plug to the seat ring, thus giving the C-seal plug seal a
predetermined permanent set. Once this is done, the plug/retainer assembly, the cage, and the seat ring become a
matched set.
With full actuator force applied and the valve plug fully seated, align the actuator travel indicator scale with the lower
end of valve travel. Refer to the appropriate actuator instruction manual for information on this procedure.
Replacement of Installed C-seal Trim
Trim Removal (C-seal Constructions)
1. Remove the valve actuator and bonnet following the appropriate instructions in the Replacing Packing section of
this manual.
CAUTION
To avoid leakage when the valve is returned to service, use appropriate methods and materials to protect all sealing
surfaces of the trim parts during maintenance.
Use c aution when removing piston ring(s) and C-seal plug seal to avoid scratching any sealing surface.